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Re: Possibility of open-sourcing GS/OS

Eric Smith wrote:

"Michael J. Mahon" <mjmahon@aol.com> writes:


So the bottom line is that, although building a RAM card for the IIgs
larger than 4MB is more complex, the 65816 _can_ directly address up
to 8MB of RAM.  That could all be used by an operating system, if
needed.



I've inquired about this before, since 8 MB RAM cards for the GS have
been sold.  Apparently using them requires some patches to the memory
manager.  There's also a problem with DMA devices (e.g., Apple High Speed
SCSI card) because DMA from the bus is only possible to the first 4MB.


Since the 8MB cards don't contain any ROM, and do not require any
software patches, I can only conclude that GSOS is already able to
manage up to 8MB unchanged.  I was aware of the DMA issue.

-michael

Music synthesis for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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